Hitherto, various attempts to multifunctionalize a polymer compound have been performed. For example, as a method for making a polymer compound having a high refractive index, the introduction of an aromatic ring, a halogen atom, or a sulfur atom has been performed. Particularly, an episulfide polymer compound and a thiourethane polymer compound in which a sulfur atom is introduced have been in practical use as a lens having a high refractive index for an eyeglass.
A number of attempts to impart heat resistance have also been performed and it is well-known that, for these attempts, a polymer compound in which an aromatic ring is introduced is applied. For example, there is disclosed a polyarylene copolymer having a substituted arylene repeating unit in the backbone thereof (see, for example, Patent Document 1). The polymer compound is expected to be applied mainly to a heat resistant plastic. There is also disclosed a polyphenylene compound obtained by a Diels-Alder reaction between a tetraethynyl compound and a bisdiene compound having a regular tetrahedron structure (see, for example, Patent Document 2).    Patent Document 1: U.S. Pat. No. 5,886,130 specification    Patent Document 2: Japanese Patent Application Publication No. JP-A-2005-232211